Regulatory Developments

On April 16, 2012, the Natural Resources Defense Council (NRDC) filed its brief in its lawsuit against the U.S. Environmental Protection Agency (EPA) concerning EPA's conditional registration for HeiQ AGS-20, an end-use product containing nanosilver. NRDC filed suit on January 26, 2012, in the U.S. Court of Appeals for the Ninth Circuit (California) against EPA, seeking to limit public exposure to the nanosilver's use in clothing, baby blankets, and other textiles and prevent EPA "from allowing nanosilver on the market without the legally-required data about its suspected harmful effects on humans and wildlife."

EPA published a February 22, 2012, Federal Register notice announcing its approval of the conditional registration for HeiQ AGS-20. According to the notice, EPA made basic health and safety determinations that show that use of HeiQ AGS-20 during the period of conditional registration will not cause any unreasonable adverse effect on the environment, and that use of the pesticide is in the public interest. Consistent with Section 3(c)(7)(C) of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), EPA determined that the conditional registration is in the public interest. According to EPA, use of the pesticide is of significance to the user community, and appropriate labeling, use directions, and other measures have been taken to ensure that use of the pesticide will not result in unreasonable adverse effects to man and the environment.

In its April 16, 2012, brief, NRDC argues that EPA's decision that HeiQ AGS-20 will not cause unreasonable adverse effects on human health was not supported by substantial evidence. According to NRDC, in calculating the risks to human health, "EPA failed to evaluate the risks to infants, even though they have an especially high likelihood of exposure to AGS-20 because they are more likely than other age groups to chew on textiles coated with it." NRDC states that had EPA properly taken infants into account, application of its own risk criteria "would have shown that AGS-20 poses unacceptable risks, and thus may have 'unreasonable adverse effects.'" NRDC further argues that EPA likewise failed to consider the risk of aggregate exposures from other nanosilver on the market. Had it done so, NRDC states, EPA's analysis would have shown that registering AGS-20 creates unacceptable risks. NRDC concludes that, because EPA's finding of no "unreasonable adverse effects" rested on "significantly understated risk assessments," its decision is not supported by substantial evidence and must be vacated.

On April 23, 2012, the International Center for Technology Assessment, Center for Food Safety, Friends of the Earth, Beyond Pesticides, Center for Environmental Health, and Institute for Agriculture and Trade Policy filed a motion for leave to file a brief as amici curiae in support of NRDC. According to the motion, counsel for amici contacted the parties seeking their consent. NRDC consented, while EPA and Intervenor, HeiQ Materials AG, took no position.

The amici argue that, as stakeholders whose organizational and membership interests will be harmed by the conditional release of HeiQ AGS-20 nanosilver pesticide products, as well as by the regulatory precedent EPA's action "sets more broadly" for U.S. oversight of nanotechnology, nanomaterials, and nanosilver pesticides, they have "a strong interest in presenting their concerns regarding the conditional registration of HeiQ, as well as offering the Court the broader 'nano-world' perspective surrounding this specific approval action." According to amici, because EPA ignored "the hundreds of other nano-silver pesticide products also available," these products will create significant aggregate exposures for which it did not account. Finally, the amici state, "EPA already has a blueprint and legal impetus for responsible oversight of these nano-silver pesticide products including AGS-20, in the form of a 2008, still-unanswered legal petition submitted to the agency by these same Amici."

On June 14, 2012, EPA filed its answering brief, arguing that NRDC lacks standing to challenge EPA's decision because NRDC has not demonstrated that it or its members face an injury that is "actual or imminent," rather than "conjectural or hypothetical." EPA states that, on the merits, its determination that HeiQ AGS-20 will not cause unreasonable adverse effects to consumers "is reasonable and supported by substantial evidence in the record." According to EPA, it "conservatively estimated potential consumer exposure to nanosilver from HeiQ AGS-20, assuming, among other things, that 35% of the silver contained in an AGS-20 treated textile that is chewed or worn could be ingested or absorbed as nanosilver, and that a three-year-old child could be exposed to a new textile daily for six months." Despite data gaps concerning HeiQ AGS-20, EPA determined it had sufficient evidence to conclude "that even a three-year-old chewing and wearing a new AGS-20 treated textile every day for six months could potentially be exposed to no more than 1/1000th of the quantity of nanosilver which did not cause any adverse health effects in relevant scientific studies." Given the low risk, EPA states that it reasonably concluded that HeiQ AGS-20 will not cause unreasonable adverse effects to consumers, and its risk assessment "warrants substantial deference from the Court."

EPA states:

Significantly, NRDC does not challenge the fact that EPA properly determined that when AGS-20 is incorporated into fibers its use will not cause unreasonable adverse effects to consumers. Rather, NRDC requests that the Court reject EPA's technical analysis and vacate EPA's conditional registration based on narrow challenges to two of EPA's MOE calculations for the use of AGS-20 as a surface coating. (Emphasis in original).

According to EPA, NRDC's claim is based on narrow challenges to two of EPA's margin of exposure (MOE) calculations for the use of HeiQ AGS-20 as a surface coating. First, NRDC argues that infants are the most vulnerable subpopulation to exposure from HeiQ AGS-20, and that if EPA's risk assessment had used the weight of a nine-month-old, EPA's oral and aggregate MOEs would have been less than the target MOE of 1,000, thereby resulting in a risk concern. EPA responds that NRDC waived this challenge because it failed to raise the issue during the public comment period. EPA maintains, however, that even if the court were to reach the merits of this challenge, EPA reasonably determined that three-year-olds, not infants, are the most vulnerable population, given certain physical and behavioral characteristics, including the fact that three-year-olds have a more developed ability to chew textiles.

Second, NRDC argues that EPA's aggregate MOE for the use of HeiQ AGS-20 as a surface coating, calculated to be exactly 1,000, compels a finding of unreasonable adverse effects for consumers because EPA should have considered the potential that consumers could be exposed to nanosilver from other products. EPA responds that this assertion is incorrect, stating "FIFRA neither requires aggregation nor specifies when aggregation might be appropriate." In this case, according to EPA, it determined that it could not aggregate exposure from other possible sources "because there was no data indicating that any other products contain nanosilver that is chemically similar to the nanosilver in AGS-20." EPA notes that this determination was consistent with Scientific Advisory Panel guidance that cautioned that "only particles of similar size and essentially identical properties can reasonably be assumed to have similar health impacts."

Amici briefs supporting EPA's position are due 14 days after June 14, 2012 or June 28, 2012.